Energy, Vol.82, 72-79, 2015
Enhancement of visible-light photocatalytic activity of Pt supported potassium niobate (Pt-KNbO3) by up-conversion luminescence agent (Er3+:Y(3)A(15)O(12)) for hydrogen evolution from aqueous methanol
In this paper, a high effective up-conversion luminescence agent (Er3+:Y3Al5O12) is synthesized by sol gel method, and then its corresponding visible-light photocatalysts (Er3+:Y3Al5O12/Pt-KNbO3) are successfully prepared by hydrothermal and direct mixing methods. For comparison, Er3+:Y3Al5O12, Pt-KNbO3 and Er3+:Y3Al5O12/Pt-KNbO3 are all characterized by XRD (X-ray diffractometer), SEM(scanning electron microscopy) and EDX(energy dispersive X-ray spectroscopy). At first, the visible-light photocatalytic activity of Er3+:Y3Al5O12/13t-KNbO3 is examined through photocatalytic hydrogen evolution from aqueous methanol solution under visible-light irradiation. Lastly, the influence factors such as Er3+ :Y3Al5O12 and Pt-KNbO3 mass ratio, heat-treated temperature and initial pH value on the visible-light photocatalytic hydrogen evolution activity of Er3+:Y3Al5O12/Pt-KNbO3 are studied. Particularly, Er3+:Y3Al5O12/Pt-KNbO3 catalysts with 0.5:1.0 mass ratio heat-treated at 500 degrees C in aqueous methanol solution with initial pH = 6.0 show the highest photocatalytic activity in hydrogen evolution from aqueous methanol solution. (C) 2015 Elsevier Ltd. All rights reserved.
Keywords:Pt-supported potassium niobate (Pt-KNbO3);Up-conversion luminescence agent;(Er3+:Y3Al5O12);Visible-light photocatalyst;Methanol splitting;Hydrogen evolution